# $Id: __init__.py 6314 2010-04-26 10:04:17Z milde $# Author: David Goodger <goodger@python.org># Copyright: This module has been placed in the public domain."""This is ``docutils.parsers.rst`` package. It exports a single class, `Parser`,the reStructuredText parser.Usage=====1. Create a parser:: parser = docutils.parsers.rst.Parser() Several optional arguments may be passed to modify the parser's behavior. Please see `Customizing the Parser`_ below for details.2. Gather input (a multi-line string), by reading a file or the standard input:: input = sys.stdin.read()3. Create a new empty `docutils.nodes.document` tree:: document = docutils.utils.new_document(source, settings) See `docutils.utils.new_document()` for parameter details.4. Run the parser, populating the document tree:: parser.parse(input, document)Parser Overview===============The reStructuredText parser is implemented as a state machine, examining itsinput one line at a time. To understand how the parser works, please firstbecome familiar with the `docutils.statemachine` module, then see the`states` module.Customizing the Parser----------------------Anything that isn't already customizable is that way simply because that typeof customizability hasn't been implemented yet. Patches welcome!When instantiating an object of the `Parser` class, two parameters may bepassed: ``rfc2822`` and ``inliner``. Pass ``rfc2822=1`` to enable an initialRFC-2822 style header block, parsed as a "field_list" element (with "class"attribute set to "rfc2822"). Currently this is the only body-level elementwhich is customizable without subclassing. (Tip: subclass `Parser` and changeits "state_classes" and "initial_state" attributes to refer to new classes.Contact the author if you need more details.)The ``inliner`` parameter takes an instance of `states.Inliner` or a subclass.It handles inline markup recognition. A common extension is the addition offurther implicit hyperlinks, like "RFC 2822". This can be done by subclassing`states.Inliner`, adding a new method for the implicit markup, and adding a``(pattern, method)`` pair to the "implicit_dispatch" attribute of thesubclass. See `states.Inliner.implicit_inline()` for details. Explicitinline markup can be customized in a `states.Inliner` subclass via the``patterns.initial`` and ``dispatch`` attributes (and new methods asappropriate)."""__docformat__='reStructuredText'importdocutils.parsersimportdocutils.statemachinefromdocutils.parsers.rstimportstatesfromdocutilsimportfrontend,nodesclassParser(docutils.parsers.Parser):"""The reStructuredText parser."""supported=('restructuredtext','rst','rest','restx','rtxt','rstx')"""Aliases this parser supports."""settings_spec=('reStructuredText Parser Options',None,(('Recognize and link to standalone PEP references (like "PEP 258").',['--pep-references'],{'action':'store_true','validator':frontend.validate_boolean}),('Base URL for PEP references ''(default "http://www.python.org/dev/peps/").',['--pep-base-url'],{'metavar':'<URL>','default':'http://www.python.org/dev/peps/','validator':frontend.validate_url_trailing_slash}),('Template for PEP file part of URL. (default "pep-%04d")',['--pep-file-url-template'],{'metavar':'<URL>','default':'pep-%04d'}),('Recognize and link to standalone RFC references (like "RFC 822").',['--rfc-references'],{'action':'store_true','validator':frontend.validate_boolean}),('Base URL for RFC references (default "http://www.faqs.org/rfcs/").',['--rfc-base-url'],{'metavar':'<URL>','default':'http://www.faqs.org/rfcs/','validator':frontend.validate_url_trailing_slash}),('Set number of spaces for tab expansion (default 8).',['--tab-width'],{'metavar':'<width>','type':'int','default':8,'validator':frontend.validate_nonnegative_int}),('Remove spaces before footnote references.',['--trim-footnote-reference-space'],{'action':'store_true','validator':frontend.validate_boolean}),('Leave spaces before footnote references.',['--leave-footnote-reference-space'],{'action':'store_false','dest':'trim_footnote_reference_space'}),('Disable directives that insert the contents of external file ''("include" & "raw"); replaced with a "warning" system message.',['--no-file-insertion'],{'action':'store_false','default':1,'dest':'file_insertion_enabled','validator':frontend.validate_boolean}),('Enable directives that insert the contents of external file ''("include" & "raw"). Enabled by default.',['--file-insertion-enabled'],{'action':'store_true'}),('Disable the "raw" directives; replaced with a "warning" ''system message.',['--no-raw'],{'action':'store_false','default':1,'dest':'raw_enabled','validator':frontend.validate_boolean}),('Enable the "raw" directive. Enabled by default.',['--raw-enabled'],{'action':'store_true'}),))config_section='restructuredtext parser'config_section_dependencies=('parsers',)def__init__(self,rfc2822=None,inliner=None):ifrfc2822:self.initial_state='RFC2822Body'else:self.initial_state='Body'self.state_classes=states.state_classesself.inliner=inlinerdefparse(self,inputstring,document):"""Parse `inputstring` and populate `document`, a document tree."""self.setup_parse(inputstring,document)self.statemachine=states.RSTStateMachine(state_classes=self.state_classes,initial_state=self.initial_state,debug=document.reporter.debug_flag)inputlines=docutils.statemachine.string2lines(inputstring,tab_width=document.settings.tab_width,convert_whitespace=1)self.statemachine.run(inputlines,document,inliner=self.inliner)self.finish_parse()classDirectiveError(Exception):""" Store a message and a system message level. To be thrown from inside directive code. Do not instantiate directly -- use `Directive.directive_error()` instead! """def__init__(self,level,message):"""Set error `message` and `level`"""Exception.__init__(self)self.level=levelself.msg=messageclassDirective(object):""" Base class for reStructuredText directives. The following attributes may be set by subclasses. They are interpreted by the directive parser (which runs the directive class): - `required_arguments`: The number of required arguments (default: 0). - `optional_arguments`: The number of optional arguments (default: 0). - `final_argument_whitespace`: A boolean, indicating if the final argument may contain whitespace (default: False). - `option_spec`: A dictionary, mapping known option names to conversion functions such as `int` or `float` (default: {}, no options). Several conversion functions are defined in the directives/__init__.py module. Option conversion functions take a single parameter, the option argument (a string or ``None``), validate it and/or convert it to the appropriate form. Conversion functions may raise `ValueError` and `TypeError` exceptions. - `has_content`: A boolean; True if content is allowed. Client code must handle the case where content is required but not supplied (an empty content list will be supplied). Arguments are normally single whitespace-separated words. The final argument may contain whitespace and/or newlines if `final_argument_whitespace` is True. If the form of the arguments is more complex, specify only one argument (either required or optional) and set `final_argument_whitespace` to True; the client code must do any context-sensitive parsing. When a directive implementation is being run, the directive class is instantiated, and the `run()` method is executed. During instantiation, the following instance variables are set: - ``name`` is the directive type or name (string). - ``arguments`` is the list of positional arguments (strings). - ``options`` is a dictionary mapping option names (strings) to values (type depends on option conversion functions; see `option_spec` above). - ``content`` is a list of strings, the directive content line by line. - ``lineno`` is the absolute line number of the first line of the directive. - ``src`` is the name (or path) of the rst source of the directive. - ``srcline`` is the line number of the first line of the directive in its source. It may differ from ``lineno``, if the main source includes other sources with the ``.. include::`` directive. - ``content_offset`` is the line offset of the first line of the content from the beginning of the current input. Used when initiating a nested parse. - ``block_text`` is a string containing the entire directive. - ``state`` is the state which called the directive function. - ``state_machine`` is the state machine which controls the state which called the directive function. Directive functions return a list of nodes which will be inserted into the document tree at the point where the directive was encountered. This can be an empty list if there is nothing to insert. For ordinary directives, the list must contain body elements or structural elements. Some directives are intended specifically for substitution definitions, and must return a list of `Text` nodes and/or inline elements (suitable for inline insertion, in place of the substitution reference). Such directives must verify substitution definition context, typically using code like this:: if not isinstance(state, states.SubstitutionDef): error = state_machine.reporter.error( 'Invalid context: the "%s" directive can only be used ' 'within a substitution definition.' % (name), nodes.literal_block(block_text, block_text), line=lineno) return [error] """# There is a "Creating reStructuredText Directives" how-to at# <http://docutils.sf.net/docs/howto/rst-directives.html>. If you# update this docstring, please update the how-to as well.required_arguments=0"""Number of required directive arguments."""optional_arguments=0"""Number of optional arguments after the required arguments."""final_argument_whitespace=False"""May the final argument contain whitespace?"""option_spec=None"""Mapping of option names to validator functions."""has_content=False"""May the directive have content?"""def__init__(self,name,arguments,options,content,lineno,content_offset,block_text,state,state_machine):self.name=nameself.arguments=argumentsself.options=optionsself.content=contentself.lineno=linenoself.content_offset=content_offsetself.block_text=block_textself.state=stateself.state_machine=state_machineself.src,self.scrline=state_machine.get_source_and_line(lineno)defrun(self):raiseNotImplementedError('Must override run() is subclass.')# Directive errors:defdirective_error(self,level,message):""" Return a DirectiveError suitable for being thrown as an exception. Call "raise self.directive_error(level, message)" from within a directive implementation to return one single system message at level `level`, which automatically gets the directive block and the line number added. You'd often use self.error(message) instead, which will generate an ERROR-level directive error. """returnDirectiveError(level,message)defdebug(self,message):returnself.directive_error(0,message)definfo(self,message):returnself.directive_error(1,message)defwarning(self,message):returnself.directive_error(2,message)deferror(self,message):returnself.directive_error(3,message)defsevere(self,message):returnself.directive_error(4,message)# Convenience methods:defassert_has_content(self):""" Throw an ERROR-level DirectiveError if the directive doesn't have contents. """ifnotself.content:raiseself.error('Content block expected for the "%s" directive; ''none found.'%self.name)defconvert_directive_function(directive_fn):""" Define & return a directive class generated from `directive_fn`. `directive_fn` uses the old-style, functional interface. """classFunctionalDirective(Directive):option_spec=getattr(directive_fn,'options',None)has_content=getattr(directive_fn,'content',False)_argument_spec=getattr(directive_fn,'arguments',(0,0,False))required_arguments,optional_arguments,final_argument_whitespace \
=_argument_specdefrun(self):returndirective_fn(self.name,self.arguments,self.options,self.content,self.lineno,self.content_offset,self.block_text,self.state,self.state_machine)# Return new-style directive.returnFunctionalDirective